kernel_optimize_test/fs/proc/uptime.c
Oleg Nesterov 1d98a5fa11 fs/proc/uptime.c:uptime_proc_show(): use get_monotonic_boottime()
Change uptime_proc_show() to use get_monotonic_boottime() instead of
do_posix_clock_monotonic_gettime() + monotonic_to_bootbased().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Tomas Janousek <tjanouse@redhat.com>
Cc: Tomas Smetana <tsmetana@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:08:02 -07:00

53 lines
1.2 KiB
C

#include <linux/fs.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/time.h>
#include <linux/kernel_stat.h>
#include <asm/cputime.h>
static int uptime_proc_show(struct seq_file *m, void *v)
{
struct timespec uptime;
struct timespec idle;
u64 idletime;
u64 nsec;
u32 rem;
int i;
idletime = 0;
for_each_possible_cpu(i)
idletime += (__force u64) kcpustat_cpu(i).cpustat[CPUTIME_IDLE];
get_monotonic_boottime(&uptime);
nsec = cputime64_to_jiffies64(idletime) * TICK_NSEC;
idle.tv_sec = div_u64_rem(nsec, NSEC_PER_SEC, &rem);
idle.tv_nsec = rem;
seq_printf(m, "%lu.%02lu %lu.%02lu\n",
(unsigned long) uptime.tv_sec,
(uptime.tv_nsec / (NSEC_PER_SEC / 100)),
(unsigned long) idle.tv_sec,
(idle.tv_nsec / (NSEC_PER_SEC / 100)));
return 0;
}
static int uptime_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, uptime_proc_show, NULL);
}
static const struct file_operations uptime_proc_fops = {
.open = uptime_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init proc_uptime_init(void)
{
proc_create("uptime", 0, NULL, &uptime_proc_fops);
return 0;
}
module_init(proc_uptime_init);